Comparative investigation of strength and plastic instability in Cu/Au and Cu/Cr multilayers by indentation
- PDF / 1,498,695 Bytes
- 8 Pages / 584.957 x 782.986 pts Page_size
- 31 Downloads / 186 Views
The mechanical response to indentation (including nano- and microindentation) has been investigated in Cu/Au and Cu/Cr multilayers with respective layer thickness ratios of 1:1 and 2:1, and individual layer thickness ranging from nanometer to submicrometer scale. It was found that the Cu/Cr multilayer has higher strength than the Cu/Au multilayer, although both multilayers have close Hall–Petch slope. Examination of indentationinduced deformation behavior shows that the Cu/Cr multilayer exhibits higher resistance to plastic deformation instability than the Cu/Au multilayer. Theoretical analysis indicates that the significant difference in mechanical response originates from the constituent layer configuration and interface structures, which impose distinguishing confining effect on dislocation activity.
I. INTRODUCTION
Nanoscale metallic multilayer often fails with premature fracture under tension or localized shear deformation under compression, even though it possesses ultrahigh strength close to 1/31/2 of the theoretical strength (E/30).1–4 For example, conventional crystalline/crystalline nanolaminates can only produce
Data Loading...
